Transmission



April 14, 1936.

F. A. PARSONS TRANSMISSION Filed June 26, 1930 4 Sheets-Sheet 1 April 14, 1936. PARSONS 2,037,263

TRANSMISSION 7 Filed June 26, 1930 4 Sheets-Sheet 2 INVE R F154 1 M5 April 14, 1936. F. A. FfARSCNS 2,037,263

TRANSMISSION Filed June 26, 1930 4 Sheets-Sheet 3 April 14, 1936.

F. A. PARSONS TRANSMISSION Filed June 26', 1930 4 Sheets-Sheet 4 Patented Apr. 14, 1936 UNITED STATES PATENT 7 OFFICE TRANSMISSION Fred AQ Parsons, Milwaukee, Wis., Kearney 8a Trecker Corporation,

Wis.

assignor to West Allis,

Application June 26, 1930', Serial No. 4cs,915 2 Claims. (01. 90-21) convenience of operation in shifting the gearing of a machine tool.

A further object is to provide means adapted to minimize the chances of error in performing such shifting.

A further object is to forming such shifting requiring efiort in their operation.

Another object is to provide a device for effecting such shifting by the manipulation of a sin le lever.

A further object is to provide such a device having an improved speed selector adjustable in advance of the shifting operation.

A further object is to provide such a. device in which the speeds to be selected are arranged in numerical order on a chart or index.

Another object is to provide improved means for adjusting the speed selector operated by power.

A further object is to provide such a device involving extreme simplicity.

A further object is to provide such a device adapted to be operated by hydraulic pressure.

-A further object is to provide such a device adapted to utilize a source of hydraulic pressure normally found in a machine of this character.

A further object is to provide a machine in which substantially the entire control is centered in a single lever.

Another object is to generally simplify and improve the construction and operation of machines of this type, and other objects and advantages will appear as the specification proceeds.

The invention consists in the construction and combination of parts as herein illustrated, described and claimed, and in such modification of the structure illustrated and described as may be equivalent to the claims.

In the drawings:

Fig. 1 is ,a left side elevation of a milling machine incorporating the invention.

Fig. 2 is a front elevation of a portion of the machine.

Fig. 3 is a sectional view on the line 3--3 of Fig. 2.

Fig. 4 is a vertical sectional view of a part'of the .machine showing the speed changing elements.

provide means for pera minimum of Fig. 5 is a vertical section taken along the line 5-5 of Fig. 4.

Fig. 6 is a plan view of a portion of the machine.

Fig. 7 is an elevation of a portion of the ma- 5 chine showing the hydraulic. means for actuating the shifting forks. v

Fig. 8 is an elevation of a housing shown attached to the machine in Figs. 4 and 5.

Fig. 9 is a. transverse section taken along the 10 line 99 of Fig. 5. v

Figs. 10, 1011 are views in section taken alone the line Ill-I0 of Fig. 5 showing the parts in different positions.

Fig. 11 is an enlarged developed view of mem- 15 bers shown in section in Figs. 5, 10, and 10a, showing the relations of certain parts to each other.

Fig. 12 is a partial sectional view on the line |2l2 of. Fig. 1 showing a control valve.

Fig. 13 is a similar section showing the valve 2 in another position.

Fig. 14 is a section on the line ll-M' of Fig. 1 showing a detail of a valve operating mechanism.

Fig. 15 is a development in part section on the 25 line l5|5 of Fig. 5.

Fig. 16 is a section on-the line l6--|6 of Fig. 7.

Fig. 17 is a sectional view of certain parts indicated in Fig. 7.

Similar reference numerals refer to like parts 30 throughout the drawings and specification.

For convenience of illustration the invention is shown incorporated in a milling machine of the type having a hollow column I, a knee 2, slidable on one face of the column, a saddle 3, horizontally 35 adjustable on the knee, and a reciprocable table 4, slidable on the saddle. The machine also has overarms 5 slidably adjustable in the upper extremity of the column, and a pendant 6 slidable on the overarms. A tool spindle I is jour- 40 naled in the column and is driven by a pulley 8 through speed changing mechanism to be presently described. A lever 9 is provided for selecting and obtaining the various'speeds and a dial I0 and pointer ll serve toindicate the speeds 45 selected.

,As shown in Figs. i and 5, the spindle is driven mechanically through a train of gears as follows: Pulley 8 is driven by a belt, not shown,- and has an elongated hub or sleeve lljournaled in a 50 suitable bearing l3 in a wall of the column I and having a gear l4 fixed on its inner end. The pulley also has an annular internal surface l5 for engaging a clutch member l6 Clutch member 16 has a hub I I which is slldably fitted on a sleeve,

to the left in Fig. 4, member |6 will be moved to the left, through the connection of pin 2| with hub 11, and will not engage surface I5. Pulley 8 will accordingly rotate freely on sleeve l8 and without driving the same. When, however, shaft 22 is moved to the right in Fig. 4, member l6 will be moved lntoengagement with surface l5 and will rotate with pulley 8. The resulting rotation will be imparted to sleeve l8 by the engagement of pin 2| with slots 28.

Sleeve |8 has gears 23 and 24 integrally or otherwise connected with each other to form a unitary member 25 slidably keyed on sleeve l8. An annular groove 26 is provided for effecting movement of said member. Gear 23 is adapted in one position of the unit to mesh with a gear 21'fixed with a shaft 28 and gear 24 is adapted in another position .of unit 25 to mesh with a gear 29 also keyed on shaft 28. Shaft 28 is journaled in suitable bearings 30 and 3| in column Triple gears 32, 33, 34 are slidably keyed on shaft 28and connected together integrally or otherwise to form a unitary member 35. A groove 36 is formed in the member to effect sliding movement thereof.

Gear 32, in one position of member 35, is adapted to mesh with and drive a gear 31 having a hub 38 rigidly'keyed on ashaft 39. Shaft. 39 is journaled in bearings 46 and 4| in the column A gear 42 is. also rigidly keyed on shaft 39 in position, to engage gear 33 in one of the positions of adjustment of member 35. Gear'42' has an elongated hub 43 extending from one side thereof and a sleeve or drum 44 having openings 45, and fixed 'on-its end remote from gear 42 a gear 46. Gear 46 is groove 48 formed in its periphery. Said spool has threaded therein a plurality of bolts 49-which are slidably fitted "i1 1.;su.itable openings in gear 42. Bolts49 engage at'ytheir ends remote from spool 41 a flange portion; 50 of. a clutch member 5| slidably mountedon the hub portion 43 of gear 42. Clutch member 5| has a groove 52 into which the ends of the bolts 49 project-and nuts 53 are provided threadedonbolts 49 foradjusting the distance between'spool 41' andclutch 5|. The

nuts may be reached for adjustment through openings 45. Clutch-5| when moved to the right in Fig. 4 by means of spool 41 and bolts 49 enages a sleeve portion 54 of a gear 55 journaled on shaft 39. Sleeve 54 enterssleeve 44, but without engaging therewith. A member 56 is slidably keyed on shaft 39 and has formed thereon gears 51 and 58. Gear 58 is adapted in one position of member 56 to engage a gear 59 rigidly mounted on the spindle 1 and gear 51 in another position of member 56 is adapted to engage a gear 68 also rigidly mounted on spindle 1. A gear 6| is rigidly mounted on spindle 1 and adapted to be driven by gear 55 at such times as the latter is clutched to shaft 39 by clutch member 5|. "The above described mechanism is adapted for changing the rate of spindle rotation, as will now be described.

Sleeve I8 is in driving relationship with shaft positioned to engage, in stillanother position of member 35, gear 34. A spool 41 is slidably mounted on the hub 38 and has a 6 adapted to connect shaft the medium of a 28 either through gears 23'and 21, orv through gears 24 and 29. With pulley 8 rotating at a constant speed, it will accordingly be possible to cause rotation of shaft 28, upon engagement of clutch l6, at two different speeds, accordingto which of the above gear pairs are in engagement. The spacing of gears 21 and 29 renders impossible the engagement-of more than one pair of gears at a time. Shaft 28 may be caused to drive shaft 39 through anyone of the three different gear pairs 32, 31; 33, 42; and 34, 46 according to the position of adjustment of member 35. Shaft 39 will accordingly have six possible speeds, three for each of the two of shaft 26. It will be understood that shaft 39 is free to turn in gear 55 at all times when clutch 5| is out of engagementwith sleeve 54. Under these conditions shaft 39 may drive spindle 1 either through gears 58 and 59, or through ears 51 and 60 according to the position of member 58. Member 56 may be moved to a neutral position in which it will engage neither of gears 59 nor 60, and at such times clutch 5| may be engaged with sleeve 54, thereby fixing gear 55 to shaft 39 and driving spindle 1 through gear 6|. The spindle may accordingly be driven from shaft 39 at any one of three different speeds for each of the six possible speeds of shaft 39 and will accordingly have a total of eighteen possible speeds relative to the pulley 8. Mechanism is provided for shifting the various members of the train and insuring the neu-. tral position of gear member 56 before engagement of clutch 5| as will be fully described presently. 3

A gear 62 is mounted on sleeve l8 and drives a gear 63 constituting part of a feed train. Gears 64 and 65 are connected with gear 63, integrally or otherwise, and journaled on a shaft 66 fixed to a bracket portion 61 of the column These gears are adapted to cooperate with a member 68, Fig. 5, comprising gears 69, 16, and 1|, slidably fixed on shaft 12 journaled in suitable bearings in a feed box 13 fixed to the column In one position of member 68, gear 69 engages gear 63. In another position gear 10 engages gear 64. and in another position gear 1| engages gear 65. These three combinations result in three differentspeeds for shaft 12, as will be understood. Shaft 12 extends outside of the feed box and has on its projecting end a universal joint 14, Fig. 4, 12 with an extensible feed drive shaft 15.

Shaft 15 drives a shaft 16 journaled in a casing 11, Figs. 2'and 3, fixed with knee 2 through universal joint 18. Shaft 16 drives a worm shaft 19 through bevel gears and 8| fixed with the respective shafts, and a worm 82 fixed with shaft 19 drives a shaft 83 through a worm wheel 84 journaled thereon and capable of being fixed therewith by means of a clutch generally denoted by numeral 85. Shaft 83 is journaled in' casing 11 and in a housing 86 fixed with saddle 3 and movable therewith, and drives a vertical shaft 81 by means of a bevel gear 88 fixed-therewith and engaging a bevel gear 89 slidably keyed to shaft 83, and vertical shaft 81 drives a table screw 96 through a reverser generally denoted by numeral 9|, Fig. 2.

Clutch comprises a member 92, Fig. 3, slidably keyed on shaft 83 and having suitable clutch gagement, when moved to the left in Fig. 3, with a gear 94 journaled on shaft 83', and having a Reverser 9| comprises bevel gears IOI, I02 having hub portions I03, I04 respectively, journaled in bracket portions fixed with saddle 3. Hub portions I03, I04 have suitable bores through which slides table screw 90, and gears IOI, I02 are spaced apart and driven in opposite directions from vertical shaft 81 by means of a bevel gear I05 fixed therewith. A clutch member I06 is' slidably keyed on table screw 90 between gears IOI, I 02 and may be clutched with one or the other by means of clutch teeth I01 and I08 formed on the clutch member and engageable with suitable clutch teeth formed on gears IOI, I02. Thus when clutch member I06 is engaged with gear IOI, table screw 90 will be rotated in one direction and when clutch member I06 is engaged with gear I02, table screw 90 will be rotated in the opposite direction, the spacing of gears IOI, I02 being such that it is impossible to engage clutch member I06 with both gears at the same time. Rotation of table screw 90 causes sliding movement of table 4, screw 90 being prevented from axially moving relative to table 4 by bearings I09I09 fixed with table 4, and engaging a nut portion I I0 fixed with saddle 3.

Means are provided for shifting clutch member I06 comprising a hand lever III fixed on a shaft I I2 journaled in suitable bearings in saddle 3 and having a lever H3 fixed therewith and engaging a groove I I4 in clutch member I06 by means of a pivoted shoe I I5.

An independent power train is provided for driving the fluid pump and rapid traverse as follows: Gear I4, Figs. 1, 4, and 5, drives a gear II6 fixed on a shaft I I1 journaled in bearings I I8 and I I9. Shaft I I1 has a gear I20 thereon, a sprocket I2I and bevel gear I22. Gear I20 is in driving relation with a gear I23 which is fixed on the drive shaft I24 of a lubricant pump I25. Sprocket I2I is connected by a chain I26, Fig. 5, to a sprocket I21 located in feed box 13 and fixed on a shaft I28 journaled in suitable bearings therein. Shaft I28 projects outside of the feed box and has a universal joint I29, Fig. 4, adapted to connect it with an extensible drive shaft I30. Drive shaft I30 actuates a shaft I3I jou'rnaled in casing 11, Fig. 3, through a universal joint I32 and shaft-I3I drives gear 94 through a gear I33 'meshing therewith and fixed with shaft I3 I Bevel gear I22 meshes with a bevel gear I34, Fig. 1, fixed on a shaft I35 extending upwardly in column I and journaled in suitable bearings I36 and I31 therein. Shaft I35 has at its upper end a worm I38 adapted to drive a worm wheel I39 formed as a part of "a clutch element I40, Fig. 5, provided with an elongated hub portion I4I journaled in a bearing I42 in column I. A shaft I43 is journaled in a suitable bore in the hub I4I for cooperation with the speed selecting mechanism, to be described presently.

The last described mechanism operates independently of the position of clutch I6, as will be understood from a consideration of Figs. 1 and 4.

Pulley 8 is integrally connected with sleeve I2 and gear I4 is fixed on said sleeve, as above described.

It follows that gear I4 runs whenever pulley 0 is driven and accordingly shaft I I1, pump shaft I24, rapid traverse shaft I28, selector drive shaft I35, and clutch element I40 all operate whenever pulley 8 is driven, regardless of the position of clutch member I6.

The pump I25 serves the double purpose of supplying lubricant to the various parts of the machine and of supplying pressure fluid to the shifting mechanism. Pump I25 draws fluid from the reservoir I44 formed in the base of the ma chine through a suction pipe I45 and forces it into a discharge port I46, Figs. 5 and 12. A branch duct I41 leads to a pressure responsive ball valve I48 and a pipe I49 leads from said valve to a perforated header I50 located in an upper part of column I. Accordingly, whenever suflicient pressure is built up in port I46, ball valve I48 opens and allows fluid to pass through pipe I49 to header I50. The fluid sprays from header I50 down over the gears and bearings in the column, finally returning to reservoir I44. The valve I46 provides for this fluid flow, but insures a sufficient pressure being maintained in port I46 capable of swinging movement adjacent the out- A spring pressed pin I53 is slidably held in the handle and holes I54-I54, Fig. 8, are provided in the wallof the box for reception thereof. Shaft I52 has fixed on its inner end a shifter arm I55, Fig. 5, provided with a pivoted shoe I56 formed to engage the sides of gear 10. Movement of handle I5I will accordingly cause, through shaft I52, arm I55 and shoe I56, shifting movement of gears69, 10, and H; and engagement of pin I53 with one or another of holes I54 will maintain the parts in shifted position, as will be understood. The shiftable elements of the spindle drive train are controlled by hydraulic means as follows r Port I46, at its upper end leads'into the casing I51 of a valve I58 which, in the position in Fig. 12, provides communication with a pipe I59, suitable couplings I60, I6I being provided to facilitate removal of the pump, and in the position shown in Fig. 13 prevents such communication. Pipe I59 leads from valve I58 to an arm I62 formed as a part of column I and rising from the lower edge I63 of an opening therein. Arm I62 has a port I64 communicating with pipe I59 and a face I65 adapted to cooperate with a pad I66, Fig. 7, formed on a cover plate I61 which is adapted to be bolted in position over the opening. A port I68 is formed in pad I66 and adapted to register with port I64 in arm I62 when'cover plate I61 is in position. Port I68 communicates with a pipe I69 which leads to a hydraulic shifting mechanism. Arm I62 and pad I66 constitute a convenient means for automatically connecting the piping of the column with that of cover plate I61 whenever the latter is placed in position on the column. Bolts I10- I10 may be fitted in bores I1II'II and may engage arm 'I62 to prevent springing thereof away from pad I66 under the influence of the hydraulic pressure.

The hydraulic shifting mechanism includes a side wall of the box.

I5I, Fig. 5, is mounted on a shown speed selector denoted generally by reference numeral I12 comprising a substantially cylindrical casing I13, Figs. 5, 7, 10, and 10a, fixed with plate I 61 and having a head I14 on its inner end. A plurality of ports I15-I15 are formed in thepart of head portion I11 and which is rotatably.

disposed in a suitable opening in head I14. A plurality of ports I 19-119 peripherially spaced apart at a predetermined distance, and grooves or channels II80, Figs. 5, 10, 10a, and 11, are provided in the face of sleeve I 16. Pipes lead from ports I15-I15 to the various elements to be actuated by the hydraulic pressure and exhaust ports I8I-I8I are formed in casing I13 adjacent to the ports I16-I15 spaced peripherially of the casing at a distance substantially less than the spacing of ports I19-I19.

A spring pressed plunger I82 engages a series of depressions I83 formed in sleeve I16 and constitutes means for yieldably locking the sleeve in various positions of rotary adjustment. Ports I19I19 and channels I80-I80 are arranged in a predetermined pattern so that for each specific position determined by plun r 8 rta ports I19-I19 will register with certain of ports I15I15 and the remainder of ports I15-I15 will be connected through channels I80-I80 with exhaust ports I8I-I8l. Pipe I69 communicates with the interior of easing I 13 through a port I84.

Accordingly, whenever valve I58 is in the positionshown in Fig. 12, fluid will flow through pipes I69 and I69 to the interior of casing I13 and sleeve I16. It will then pass through whatever of ports I19-I19 are in registry with any of ports the shifting apparatus. Fluid returning through other pipes to ports I15'I15 in response to the shifting action will be conducted through certain of channels I80I80 to the adjacent exhaust portsand discharge into the interior of column 1;

No pressure fluid will escape from the interior of sleeve I16 through any of the exhaust ports because of the spacing of the same relative to the spacing of ports I8II8I whereby in any of the adjusted positions determined by plunger I82, the exhaust ports I8I-I8I will lie between and to one side of ports I19I19 and be closed by the imperforate wall of sleeve I16. Furthermore, each'exhaust port is located in a plane between the planes of adjacent sets of ports I'I9-I19, as shown in Fig. 11, whereby there will be no position in which any of ports I19I19 will register with any of exhaust ports I 8I-I8I. It will thus be seen that means are provided in the form of selector I12 for readily supplying pressure fluid to any desired combination of shifting devices and exhausting any fluid returning from any shifting devices as a result of shifting movement thereof, merely by causing rotation of sleeve I16 to the proper adjusted position.

As above described, the double gear member 25 has two positions for producing two speeds in shaft 28. For shifting this member a shifter fork I85, Fig. 5, is provided pivoted on a stud I86 fixed with a bracket portion I 81 fixed with column I, and having enlarged portions I 88-l 88 engaging groove 26. The fork member at its opposite end is formed as a gear sector I89 and engages rack teeth I90, Fig. 7, formed on a plunge- I9!.

Plunger I'll is fitted at its ends into cylinders I92 and I93 fixed with cover plate I61. Cylinder engagement of gear 23 with gear 21.

responding position of selector sleeve I16 will be such as to cause registration of one of ports I19 with the port I15 connected with pipe I94 and registration of a. groo 3: I80 with port I15 connected with pipe I95.

Thus when valve I68 is in the position shown in Fig. 12, fluid pressure will be transmitted through -pipes I69 and I69 to selector I12 and from there through pipe I94 to cylinder I92, thus moving plunger I 9| to the right. Fluid already in cylinder I93 will pass through pipe I95 and one of grooves I80 to one of the exhaust ports I8I and be discharged. Movement of plunger I9I to the right in Fig. 7 will through the pivoted shifter fork I cause movement of gear member 25 to the left in Fig. 4 and consequent On the contrary, when a spindle speedis desired requiring the engagement of gear 24 with gear 29, sleeve I16 will be rotated to such a position that pressure will be transmitted in the above manner throughpipe I96 to cylinder I93, while cylinder I92 will be connected through pipe I94 with an exhaust port I8I. Plunger I9I will accordingly move to the left in Fig. 7 and cause movement of member 25 to the right in Fig. 4.

Triple gear 35, as described above, has three possible positions and thus requires a shifting device differing somewhat from the above as follows: A shifting arm I96, Fig. 5, is provided fixed on a shaft I91 journaled in a suitable bearing in cover plate I61 and having a pivoted shoe I98 engaging groove 36, Fig. 4. A gear segment I99 is formed on arm I96 and engages rack teeth 200 in a plunger 20I, Figs. 5, 7, and 15. Plunger 20I has a V-shaped recess 202 in a side thereof and is reciprocably fitted in cylinders 203 and 204, fixed with cover plate I61. A third cylinder 206 is fixed with cover plate I61 and has a plunger 206 having a wedge-shaped end portion 201 cooperating with the recess 202 in plunger 20I. A pipe 208 connects cylinder 203 with one of ports I 15 of selector I12 and a pipe 209 connects cylinder 204 with another of ports I16 while a pipe 2I0, Fig. 7, connected with a port 2 leading from cylinder 205 leads to another of ports I15.

.requires the engagement of gear 32 with gear 31, fluid will be directed into pipe 208 and cylinder 203 in the manner above described, while pipe 209 and cylinder 204 will be connected with one of exhaust ports I8I. Pipe 2"! will also be connected with an exhaust port and plunger 20I will be moved to the right in Fig. 7 causing shifting of gear member 35 to the left in Fig. 4.. It will be apparent from a consideration of Fig. 15 that any movement of plunger MI in either direction from its mid-position will cause movementof plunger 206 to the left in Fig. 15. Any fluid in cylinder 205 will under these conditions escape through port 2 and pipe 2I0 into one of exhaust ports I8I. If the desired spindle speed calls for the engagement of gears 34 and 46, Fig. 4, fluid will be transmitted through pipe 209, Fig. 7, and exhausted through pipe 208 and plunger 20I will be moved to the left with resulting movement to the right in Fig. 4 of member 35.

Assuming the parts in-the position shown in Figs. 4 and 7, when a spindle speed is selected requiring the engagement of gears 33 and 42,

fluid pressure will be transmitted through pipe '2I0 to cylinder 205, while both pipes 208 and 209 will be put in communication with exhaust ports I8I. Motion of plunger 206 to the right in Fig. 15 will accordingly take place and owing to the angularity of portion 201 and recess 202, plunger 20I, arm I96, and gear member 35 will be shifted to their respective mid-positions and the desired gears engaged.

It is apparent that during this movement either cylinder 203 or 204 might draw air in through its exhaust port with disadvantageous results, and to guard against this there is provided a reservoir 2l2, Figs. 10 and 10a, designed to retain at all times a small quantity of the fluid exhausted from the various shifting devices, and to overflow when full. Short lengths of pipe 2I3 lead from exhaust ports I8I to points well below the surface of the fluid in the reservoir; .Consequently whenevera negative state of pressure ocours in any cylinder connected with an exhaust exhausted from cylinders 228 and 232, plungerand 228, plunger 229 port, it will draw fluid and not air into the system.

As outlined above, gear member 56 is susceptible of three positions, one in which gear 58 engages gear 59, and one in which gear 51 engages gear 60, and a third or neutral position in which the above gears 51 or 58 engage neither gear 59 or 60. For shifting member 56 there is provided a device including a shifter fork 2I4 engaging an annular groove 2I5 formed between gears 51 and 58, the fork having an apertured portion 2I6, Fig. 7, slidable on a guide rod 2 fixed in brackets 2I8-2I8 rigid with cover plate I16. A pin 2I9 is fixed on apertured portion 216 and engages a slot 220 formed in a pivoted arm 22I. The arm is pivoted on a stud 222 fixed with a cover plate I61 and has a gear sector 223 meshing with rack teeth 224- formed in a plunger 225. Plunger 225 has a V-shaped recess 226 and is reciprocably fitted in cylinders 221 and 228. A plunger 229 having a wedge-shaped end portion 230, Fig. 17, cooperating with the V-shaped recess 226 in plunger-225 and a port 23I therethrough is slidably fitted in a cylinder 232 disposed axially at right angles to cylinders 221 and 228. Cylinder 221 has a pipe 233 for supplying and exhausting fluid, and cylinder 228 has a pipe 234 for a similar purpose. Cylinder '232 has a pipe 235 for supplying and exhausting fluid in .a similar. manner.

Cylinder 232 has ports 2 36 and'231 in the wall plunger 229 under certain conditions, as shown in Fig. 17. -It will be apparent that when fluid is admitted to cylinder 228 and exhausted from cylinders 221 and- 232, plunger 225 will move to the left, as shown in Fig. '7, and gear 58 will be shifted into engagement with gear 59. At the same time plunger 229 will be forced upwardly owing to the angularity of portion 230 and recess 226. when, however, fluid is admitted to cylinder 232 and exhausted from cylinders 221 will be forced downwardly and, owing to the aforesaid angularity of portion 230 and recess 226,'plunger 225 will be forced to take a central position and gear member 56 will be shifted to neutral.

When fluid is admitted'to cylinder 221' and 225 will-be moved to the right and gear 51 will beshifted into engagement with gear 60. At the same time, owing to the ang'ularity of portion 230 and recess 226', plunger 229 willbe moved mechanism before a full understanding can be had of the operation of the former. A

Clutch 5|, as above described, can be shifted into and out of engagement with sleeve 54 by means of spool 41 and bolts 49". A shifter fork 238 engages groove 48 of the spool and is fixed at its end remote therefrom on a plunger 239, Figs. 5 and 7, slidably'fitted in cylinders 240 and 24 ,I, fixed on cover plate I61, and having fluid pipes 242 and 243 respectively. A plunger 244 is fitted in a cylinder 245'axia11y at right angles.,.to plunger 239 and having a wedge-shaped end portion 246 cooperating with an angular recess 241 in said plunger. ,Cylinder 245 has a fluid pipe 248 leading to one of ports I15. It will be seen that whenlfluid is transmitted through pipe 242 to cylinder 240 and cylinders 24I and 245 are connected with the exhaust ports, plunger 239 will be moved to the right in Fig.7 and plunger 244' will be forced downwardly.

The movement of plunger 239 will engage clutch 5| through fork 238. If now pressure is transmitted to cylinders 2H and 245 through pipes 243 and 24,8, plunger 239 will be moved to the left and plunger 244 will be raised. Plunger 244 has ports 249 and 250, therethrough adapted to registerqwhen the plunger is in its uppermost position with ports 25I, 252, Fig. 16, and with ports 253, 254,'respectively, of cylinder 245. A.

pipe 255 connects oneof ports I15 of the selector with port 25I and another pipe 256 connects another of ports I15 with port 253. Pipe 233 con-' nects with the port252 and pipe 234 connects with port 254. Pipe 242 connects with port 231 .of cylinder 232 and a pipe 251 connects the remaining port I15 with port 236.

As stated above, it is important that gear. member 56. be shifted to its neutral position before clutch 5I is engaged and also that clutch 5| be disengaged before gear member 56 is shifted out This sequence of events. is insured by the action of plungers 229 and 244 of its neutral position.

with their ports as follows:

Assuming the parts in the position shown in Fig. 4, and that selectog I12 is adjusted for a spindle speed requiring t e engagement of clutch 5|, the pattern ofthe ports I19 and grooves I80 is such that fluid, 'when admitted to the selector by valve I58, will be transmitted to pipes 235 and 251, Fig. 7, while pipes 243, 248, 255, and 256 will be connected to their exhaust ports m. At this point the flow of fluid will be interrupted bythe non-registration of ports 236 in cylinder 232 and 23I in plunger 229. Plunger 229 under the influence of pressure communicated through 'pipe .235 will move downwardly and in so doing will cause, through the angularitybf its end portion 230-and recess 226-; plunger 225 to move to the .noted that at this time plunger 244 is in its uppermost position so that ports 249 and 250 are in registration with ports 25I, 2525253, and 254, respectively.

When, however, plunger 229 has reached the limit of its down stroke, as shown in Fig. 17, gear member 56 will have reached its neutral position and it will be permissible for clutch 5| to engage. At this time port 23I will register with ports 236 and 231 and thus allow fluid to flow from pipe 251through the ports to pipe 242 and into cylinder 249. Plunger 239 will accordingly be forced to the right engaging the clutch through the fork 238. Fluid in cylinder 24| will escape to the exhaust through pipe 243. Plunger 244 is forced down by the motion of plunger 239, owing to the angularity of portion 246 and recess 241, while fluid in cylinder 245 escapes through-pipe 248 to one of the exhaust ports. Thismovement throws ports 249 and 259 out of registration with ports 25I, 252, and 253, 254, respectively, and prevents any flow of fluid in pipes 233 and 234, thus locking plunger 225 in its mid-position and gear member" 56 in its neutral position at all times when clutch 5| is engaged. This locking action is in addition to that of plunger 229 acting in the recess 226 and persists even at times when there is no'fiuid'pressure in cylinder 232.

Assuming now the plunger 225 in mid-position and plunger 239 in its right-hand position, gear member 56 in neutral and clutch 5| engaged, plunger 229 will be down and port 23I in registration with ports 236 and 231 and plunger 244 will be down and ports 249 and 259 out of registration with ports 25I,' 252, and 253, 254, respectively. As outlined above, it is important that clutch 5| be disengaged"from gear 55 before gear member 56 is shifted from its neutral position. Assuming also selector I12 adjusted for a spindle speed requiring the engagement of gears 58 and 59, fluid pressure will be admitted to pipes 243, 248, and 256 and pipes 242, 235, and 255 will be put into communication with exhaust ports I8I.

At'this point communication of pipe 256 with pipe 234 and of pipe 255 with pipe 233 is cut off by the non-registration of ports 249 and 259 with ports 25I, 252, and 253, 254, respectively. It is accordingly impossible for plunger 225 to move from its mid-position or for gear member 56 to shift from neutral until plunger 244 has been permitted to rise through movement of plunger 239 and consequent disengagement of clutch'5I.

However, fluid will pass through pipe 243 into cylinder 24| and move plunger 239 to the left, while fluid in cylinder 249 will pass through pipe 242, port 23I and pipe 251 to on'eof the exhaust ports I8I. At the same time fluid will pass through pipe 248 into cylinder 245 and raise plunger 244 as plunger 239 moves. As soon as plunger 239 has moved sufllciently to disengage clutch 5 I, plunger 244 will have moved sumciently to bring about registration of ports 249 and 259 with ports 25I, 252, and 253,254, respectively. Fluid will then flow through pipe 255, port 259 and pipe 234, forcing plunger 225 to the left and shifting gear 58 into mesh with gear 59. Fluid in cylinder 221 will in the meantime escape through pipe 233, port 249 and pipe 255 to one of exhaust ports I8I. Such motion of plunger 225 will cause upward movement of plunger 229 and consequent non-registration of port 23I with ports 236 and 231. This negatives the possibility of fluid finding its way into cylinder 249 and causing engagement member 258, Figs. 5 and 6, slidably keyed on shaft I43 and having a conical friction face 259 for engaging clutch element I49, whereby to cause rotation of shaft I43 and sleeve I16. Shaft I43 extends outside of column I and dial I9 is fixed therewith so as to indicate at all times the position of sleeve I16.

Hand lever 9 is fixed on a shaft 269 journaled in column I and extending inside thereof and causes vertical movement of a rod 26I through pivotal connection with an arm 262 fixed on the inner end of shaft 269. Rod 26I moves clutch member 258 into and out of engagement with element I49 by means of a lever 263, Fig. 5, fixed with a shaft 264 journaled in suitable hearings in column I. Lever 263 engages a pair of adjustable collars 265265 on rod 26I for actuation thereby.

,A'fork 266 is fixed with shaft 264 and engages a spool 261 formed on member 258 by means of pivoted shoes 268-268. Upward movement of lever 9 will accordingly cause engagement of clutch member 258 with element I49. Accordingly, when it is desired to change the adjustment of sleeve I16, it is merely necessary to raise lever 9 and watch dial I9 until the desired speed indication appears opposite pointer II, when lever 9 may be lowered and clutch member- 258 disengaged from element I49 and the motion stopped. The parts will be locked in their adjusted position by spring pressed plunger I82 engaging one of the recesses I83. The spring on plunger I32, however, is not powerful enough to interfere with the action of the clutch just described.

Rod 26I also operates valve I58 by means of a pin 269, Fig. 14, engaging a slot 219 in a lever 21I fixed with a shaft 212 journaled in a bracket 213 flxed'with column I. gear sector 214 fixed thereon and engaging a gear 215 fixed with the stem 216 of valve I58 projecting outside of ,casing I51. Movement of rod 26I up or dow'nwill accordingly cause rocking of lever 21I andsector 214 with consequent rotary movement of valve I 58. The proportions of the valve I58, gear 215, sector 214 and lever 21I are such that valve I58 will provide communication between port I46 and pipe I59 at all times except when lever 9 is in its upper position and clutch member 258 is engaged with element I49.

Rod 26I actuates the main clutch I6 through rod 22 by means of a lever 211 engaging a spool 218 on shaft 22. Lever 211 is fixed with a shaft 219 rotatably supported from column I and having alever 289, Figs. 1 and 6, fixed therewith. Lever 289 engages a pair of adjustable collars 28 I-2 81 adjacent the lower end of rod' 26 I whereby upward motion of rod 26I will cause movement of shaft22 to the right in Figs. 1 and 4 and engagement of clutch I6, while downward movement of rod 26 I will cause movement of shaft 22 to the left and disengagement of, clutch I 6.

The collars on rod 26I are so adjusted that clutch 258. is engaged when rod 26I is in its lowermost position, while valve I 58 is closed and clutch I6 is disengaged, and when rod 26I is in an intermediate position, clutch 258 is disengaged, valve I 58 is open, and clutch I6 is disengaged, and when rod 26I is in its uppermost position, clutch 258 is disengaged, valve I 58 is open and clutch I6 is engaged. l

These positions of rod 26I are the reverse of K the positions of lever 9 owing to the action of arm 262, and accordingly raising lever 9 operates to cause rotation of the selector, while lowering it part way operates to cause shifting of the speed change elements-into the position combinations which will produce the spindle speed indi-' cated on dial I9, and moving it to its lowest position starts the spindle in operation. A spring 282, Fig.v 6, slidably fitted in a part of column I cooperates with recesses 283 and 284, Fig. 1, in lever 9 to yieldably lock the same in its intermediate and lowermost positions. No provision is made for locking the lever in its upper position, since it is never desirable to maintain clutch 258 engaged for longer than necessary to adjust selector I12, and it gives the operator better control of the selecting action to have the lever freely movable during this operation.

It will be apparent that the ports I19 and grooves I80 can be arranged in any pattern desired and in practice they are so arranged that successive positions of adjustment of sleeve I16 will cause shifting of such speed change elements into such positions as will be productive of successive speeds in spindle I. Dial I is accordingly calibrated to read 'directly in spindle revolutions per minute and the readings are consecutive from the lowest to the highest at which spindle I may be driven.

It may be noted that important that the power for operation of the selective and shifter devices of the rate changer control shall not be interrupted during any operation of the machine. The power trains for these devices are therefore each driven from a point in the transmission which excludes the main clutch consisting of member l6 and associated parts and which also excludes the rate changer consisting of various shiftable elements since either the main clutch or the rate changer might otherwise act as motion interrupters.

For manual movement of table 4, a crank, not shown, may be applied to a squared portion 295 of table screw 90. Knee 2 may be raised and lowered by a suitable elevating screw 286, Fig. 1, engaging a threaded pedestal 281 and supDOrting the knee by means of a bearing 283. Screw 286 may be turned by a crank or the like, not shown, applied to the squared portion 289 of a shaft 290 journaled in knee 2 and driving screw 286 by pressed plunger means of bevel gears 29 l, 292, fixed with the shaft and screw, respectively, and saddle 3 may be moved horizontally on knee 2 by means of a screw 293 journaled in the knee andprevented from axially moving therein and engaging a nut portion 294 fixed with saddle 3. Screw 293 may be turned by a suitable crank, not shown, applied to squared portion 295 of screw 293.

The above being a complete description of an embodiment of the invention.

What is claimed is: 1

1. In a milling machine, the combination of a base, a tool spindle rotatably supported from said base, a work table supported from said base for movement in a direction transverse to the spindle axis, a power source driven at a substantially confor various reasons it is stant rate, a feed train driven from said source for relative bodily movement of said spindle and table, a spindle rotating train driven from said source, a main clutch operable for interrupting both said trains, said spindle train including a rate changer having a plurality ofgear elements shiftable into various position combinations collectively giving rise to a fast speed, a relatively slow speed and a plurality of intermediate speeds of said spindle; and control mechanism for said spindle train including a shifter operable to move said shiftable elements into said various position combinations one at a time, a train driven from said power source exclusive of said main clutch and connectible to operate said shifter, a lever manuallyoperable to control the connection of the last mentioned train with said shifter, and speed selective means associated with said shifter including a chart having numerical markings respectively corresponding to different of said spindle speeds and an indicator movable relative to said chart in accordance with the element positioning effect resulting from operation of said shifting means.

2. In a milling machine, the combination of a rotatable tool spindle, a work support adjacent said spindle and reciprocably movable in a path transverse to the spindle axis, a substantially constant speed power source, a spindle train driven from said source and including a rate changer providing a number of gear elements shiftable into various position combinations respectively efiective for different spindle speeds, a

feed train for said work support and including a rate changer adjustable for a variety of relativelyslow feed rates of support movement, clutch means operable to simultaneously interrupt both said trains, a first train driven from said power source to exclude said clutch means and each of said rate changers and connectible for a relatively fast rate of support movement, a second train driven from said power source 'to exclude said clutch means and both said rate changers and control mechanism for said milling machine including a fluid operable gear shifter operable to shift the gear elements of said spindle train rate changer out of any of said position combinations into any other thereof, a pump driven from said second train and connectible to operate said gear shifter, selective valve means associated with said pump and shifter and adjustable to predetermine a position combination which will result from shifter operation and in advance thereof, and other valve means operable independently of the first mentioned-valve means for connecting said pump to operate said. shifter. 

